Month: September 2022

TCP GENES. These are developmental transcription factor genes found only in vascular plants, involved in the evolution of key morphological features. https://en.m.wikipedia.org/wiki/TCP_protein_domain View in LinkedIn

SNAPDRAGON CANDIDATE GENE EXAMPLE. "For example, changes in the expression of the TCP gene lineage during floral development of Antirrhinum were shown to cause alterations in petal morphology in this model species, resulting in a shift from bilaterally symmetrical to radially symmetrical flowers." https://lnkd.in/dD4GcAS View in LinkedIn

FLOWER SYMMETRY. "Subsequent studies demonstrated that this same class of genes was responsible for the evolution of symmetry across many lineages of flowering plants, with similar yet independently evolved genetic mechanisms underlying differential gene expression patterns." https://lnkd.in/dD4GcAS View in LinkedIn

WIDESPREAD CANDIDATE GENE. "A relationship was drawn between the differential expression of the TCP developmental gene(s) and phenotypic variation associated with fixed morphological diversification across angiosperm flowers. This fixed diversity is demonstrated across large evolutionary distances and across floral organ types, demonstrating the conserved nature of the TCP gene lineage and its role in floral symmetry patterns." https://lnkd.in/dD4GcAS View in LinkedIn

CANDIDATE GENE QUESTIONS. "What is not clear from these studies, however, is the diversity of mechanisms by which the TCP genes may underlie changes in floral symmetry across these diverse lineages, or the selection process by which the genetic modifications underlying shifts in patterns of symmetry occurred." https://lnkd.in/dD4GcAS View in LinkedIn

DOWNSTREAM OF THE CANDIDATE GENES. "While the expression of TCP genes is spatially restricted in similar ways in groups in which bilateral symmetry has evolved independently, the expression patterns are not identical for each evolutionary event. Additionally, TCP gene expression is acting to regulate a cascade of genes that vary in their copy number and expression patterns." https://lnkd.in/dD4GcAS View in LinkedIn

GENE NETWORKS BEAT CANDIDATE GENES. "Studies in both model systems and in diverse plant lineages have demonstrated that floral morphology is not controlled by a single candidate symmetry gene or even a single set of genes, but rather by a complex network of genes that regulate symmetry patterns and lead to the diversity in shape within lineages." https://lnkd.in/dD4GcAS View in LinkedIn

UNDERLYING NUANCES. "Differential expression and interactions of the network genes can underlie symmetry differences among flowers by influencing characters such as petal shape, stamen growth and cell type differentiation within flowers and lineage-specific changes in copy numbers of these genes, each copy having the potential to acquire mutations in regulatory or coding regions, provide opportunities for novel developmental and morphological consequences." https://lnkd.in/dD4GcAS View in LinkedIn

GENE NETWORKS FOR ADAPTATION. "In order to study the genetics of adaptation in floral form, the full developmental networks underlying organ morphology must be determined for the lineage under study. Using a comparative approach among related species or within polymorphic populations, mutation(s) causing an observed change in gene expression or alterations in protein interactions can be identified." https://lnkd.in/dD4GcAS View in LinkedIn

MORE COMPLEX THAN JUST CANDIDATE GENES. "In many cases, differential copy numbers of the genes involved in the networks may contribute to a shift in timing or placement of gene expression, resulting in novelty in form. Thus, both regulatory changes as well as novel or altered DNA binding and/or protein interactions (i.e. coding changes) must be investigated." https://lnkd.in/dD4GcAS View in LinkedIn